Type disc with integral coupling device

ABSTRACT

A low cost, one piece, plastic coupling having inherent springlike qualities for quickly connecting and disconnecting a printing disc to a printing machine. The coupling is molded of a plastic having a memory in order to provide a positive springbiased connection. The coupling is attached or made integral with the printing disc and is operable by applying finger pressure to one end of the coupling causing two flexible extensions to bend. Securing hooks of the coupling can then be easily engaged to, or disengaged from, a drive shaft of the printing machine.

United States Patent [191 Orlens et al.

[ 1 Apr. 22, 1975 TYPE DISC WITH INTEGRAL COUPLING DEVICE [75]Inventors: Alfreds Orlens, Old Greenwich;

William W. Coville. Stamford. both of Conn.

[73] Assignee: Pitney-Bowes, Inc., Stamford Conn.

[22] Filed: Nov. 23, 1973 [21] Appl. No.1 418,291

[52] U.S. Cl 197/53; 197/l8 [51] Int. Cl B4lj H24 [58] Field of Search197/18, 52, 53, 54, 6.7

[56] References Cited UNlTED STATES PATENTS 3.272.30l 9/l966 Craigl97/6.7 3.481.2ll l2/l969 Bottazzi l97/67 X OTHER PU BLICATlONS IBMTech. Disclosure Bulletin, Vol. 13, No. 1. June Primary Examiner-EdgarS. Burr Assistant Examiner-R. E. Suter Attorney. Agent, 0" FirmWilliamD. Soltow, .lr.; Albert W. Scribner; Robert S. Salzman [57] ABSTRACT Alow cost. one piece. plastic coupling having inherent spring-likequalities for quickly connecting and disconnecting a printing disc to aprinting machine. The coupling is molded of a plastic having a memory inorder to provide a positive spring-biased connection. The coupling isattached or made integral with the printing disc and is operable byapplying finger pressure to one end of the coupling causing two flexibleextensions to bend. Securing hooks 0f the coupling can then be easilyengaged to, or disengaged from. a drive shaft of the printing machine.

3 Claims, 6 Drawing Figures TYPE DISC WITH INTEGRAL COUPLING DEVICE Thisinvention pertains to a flexible plastic coupling. and more particularlyto a flexible coupling for quickly connecting or disconnecting aprinting disc from the hub of a printing machine.

BACKGROUND OF THE INVENTION In printing devices of all kinds. it ishighly advantageous to be able to replace worn parts. and performmaintenance with rapidity. Very often it is the small operativefeatures. which dictate public acceptability. For example. the ease ofreplacing a used ribbon in a typewriter without dirtying one's hands.has been known to have greatly influenced the sale of that particularmodel.

In the case of high speed quality printing devices the ease ofmaintenance is a highly significant selling point. High speed qualityprinting generally produces a sizable degree of wear upon the partsofthe machine. thus requiring frequent maintenance. The parts which aremost frequently needing replacement in serial printers are the ribbonand printing disc. Therefore. it is desirable to be able to easilyreplace a printing disc. It is also desirable for an operator to have aset of easily assembled discs each having a different style or font ofcharacters for different printing situations. such as discs havingdeluxe type. pica type. elite type. etc.

This invention seeks to provide a low cost coupling which allows forrapid assembly and replacement of a printing disc in a serial printingmechanism.

SUMMARY OF THE INVENTION This invention is for a one-piece flexibleplastic coupling which is attached to a printing disc. and which allowsthe printing disc to be quickly and easily connected or disconnectedfrom a rotative hub of a print ing machine.

The hub of the printing machine is provided with an abutting surfaceover which the coupling rides. and is allowed to snap-fit into place.The coupling comprises a center section which seats upon the hub member.From the center section. there extends to radially projecting flexiblearms. The arms have a flexible springlike resiliency, which enables themto bend and flex. This inherant flexibility is due to the memoryqualities of the plastic material. Materials commonly exhibiting thedesired flexibility and memory are for example: acetal homopolymer.acetal copolymer. and polypropylene.

Each flexible arm supports a rigid flange at its outer end. The flangeis disposed opposite the center section and has a finger engageable end.and a coupling. hooklike end. The hook-like ends of the rigid flangeride over-the hub abutment and snap into place. This is accomplished bymeans of depressing or pushing upon the finger engageable ends of theflange. so as to cause the flexible arms to bend. When the arms are madeto bend, the hook-like portions of the flanges ride over the abutment ofthe hub. The coupling is then securely locked into place.

It is an object of the invention to provide an improved easilyconnectable and disconnectable coupling;

It is another object of this invention to provide a means of easilyassembling or replacing a printing disc in a printing machine;

It is a further object of the invention to provide a couplingarrangement for a printing disc. which is of low cost. one-piece.plastic construction.

These and other objects of this invention will become moreunderstandable. and will become more apparent with reference to thefollowing detailed description. taken in conjunction with theaccompanying drawings. in which:

FIG. 1 is a prospective view of the inventive printing and couplingassembly of this invention shown in the unassembled state;

FIG. 2 is a side view of one embodiment of the coupling of FIG. 1 shownbeing assembled;

FIG. 2b is a side view of the coupling of FIG. 2a shown in its assembledstate;

FIGS. 3a through 30 are side views of a second embodiment of thecoupling of FIG. 1, shown in three different stages of assembly.

Generally speaking. the invention is for a one-piece flexible plasticcoupling which is either attached to. or integrally formed with. aprinting disc. The coupling is designed to quickly connect or disconnectthe printing disc to and from a rotative hub of a printing machine. Thehub has an abutting surface with which the coupling is engageable. Thecoupling comprises a center section which seats upon the hub of theprinting machine. At least one flexible arm member extends outwardlyfrom the center section. The flexible arm has a spring-like resiliencywhich enables it to bend and flex in a spring-like manner. Asubstantially rigid flange is disposed upon the flexible arm memberopposite the center section. The flange has a finger engaging end and acoupling end. The finger engaging end is adapted to receive pressureapplied to it by the finger of an operator. This finger pressure causesthe flexible arm member to flex and bend. The coupling end of the flangerides over the abutting surface of the hub during assembly, when thecenter section of the coupling is caused to be seated upon the hub. andthe flexible arm is caused to bend. The printing disc locks upon therotative hub of said printing machine after the coupling end of theflange rides over the abutting surface of the hub.

Now referring to FIG. I, the printing disc assembly of this invention isshown in the unassembled state. A printing disc 10 having a plurality ofradially extending arms 11 is depicted. Each of the arms 11 are flexibleand carry a character type 9 at their ends. A center section of the disc10 supports a coupling illustrated generally by arrow l2. Thecoupling-l2 has a bore 14 which seats (arrow 13) upon a hub 15. The hub15 is part of the drive shaft 16 of the rotative drive mechanism of aprinting machine. The hub 15 also comprises a disctype flange section 17having two notches l8 and 19. respectively. cut therein. The notches l8and 19 receive rigid flange members 20 and 21. respectively. of thecoupling 12. Coupling 22, hook-like ends of the flange members 20 and 24ride over the abutting surfaces 23 of the notches l8 and 19 and lock ona rear surface of disc 17.

The flange members 20 and 21 are respectively supported upon twoflexible arm members 24 and 25, as shown.

The coupling 12 is molded in one-piece. of a plastic material exhibitinga memory. The flexible arms 24 and 25 are molded in thin enoughcross-section. so that they exhibit flexibility. and because of thememory characteristics of the plastic. will also exhibit a springlikeresiliency. Therefore. if the arms 24 and 25 are caused to bend. theywill flex in a spring-like manner. The flange members 20 and 21 aremolded in a thicker cross-section than the arms 24 and 25, and aretherefore. substantially rigid.

The flanges 20 and 21 each have a finger tab 26, which can be depressed(Sec FIG. 2) so as to lift the hook-like ends 22 over the abuttingsurfaces 23. The finger tabs 26 may also be pushed (arrow 13) towardsthe drive shaft 16. This will cause the inclined surface 27 of thehook-like ends 22 to advance upon abutting surfaces 23, resulting in thespreading apart of the flange members 20 and 21 about their hooked ends.This will allow the hook-like ends 22 to ride over the abutting surfaces23 (See FIG. 3a).

The notches l8 and 19 are of unequal size. as are the respectivematching flanges 20 and 21, and hence the printing disc 10 can be putupon the shaft 16 in only one set position.

FIG. 2a and 2b illustrate one embodiment of the inventive coupling. InFIG. 2a. the coupling 12 is shown being inserted upon drive shaft 16.The finger tabs 26 of the flanges 20 and 21 are depressed (arrows 28) byapplying finger pressure thereto. This causes arms 24 and 25 to flex asshown. which causes hooks 22 to spread apart from each other (arrows29). Hook-like ends 22 now have sufficient clearance to overrideabutting surfaces 23 of the notches l8 and 19 respectively.

When the coupling 12 is completely seated upon the drive shaft 16, (FIG.2b) the finger pressure on the tabs 26 is released. This causeshook-like ends 22 to move toward each other. (arrows 30) becauseresilient arms 24 and 25 of the coupling will now tend to return totheir unflexed condition.

The hook-like ends 22 will now come to rest upon the beveled surfaces 31as shown in FIG. 2b. The coupling 12 is now locked upon drive shaft 16.The arms 24 and 25 still exert a certain amount of flexural force uponflanges 20 and 21, and hence. upon hook-like ends 22,

so that hook-like ends 22 tend to remain locked upon beveled surfaces31.

FIGS. 3a through 30 show a second embodiment of the coupling of thisinventive printing disc. As can be seen from FIG. 3a, when the coupling12 is completely seated upon drive shaft 16, the hook-like ends 22 ofthe flanges 20 and 21 rest upon abutting surfaces 23. Abutting surfaces23 in this embodiment do not contain beveled surfaces 31 as shown inFIGS. 2a and 2b.

In order for the coupling 12 to become locked upon shaft 16, thehook-like ends 22 must be made to ride over abutting surfaces 23, andlatch behind them upon surfaces 32 as shown. Because the arms 24 and 25are in a flexed condition when hook-like ends 22 are upon abuttingsurfaces 23, (FIG. 3a) the hook-like ends 22 will tend to move towardeach other as they ride past surfaces 23. This will cause the hook-likeends 22 to firmly anchor upon surfaces 32, and thus. cause the coupling12 to lock upon shaft 16.

The above locking condition is accomplished by causing finger pressureto be applied upon tabs 26 as shown by arrows 33 in FIG. 3a. Tabs 26 arepushed toward drive shaft 16, causing hook-like ends 22 to ride overabutting surfaces 23 as illustrated in FIG. 3b. The hook-like ends 22will now move toward each other as shown by arrows 34, thus locking thembehind surfaces 32.

When tabs 26 are caused to be pushed as depicted in FIG. 3a. theflexible arms 24 and 25 will be caused to flex in an opposite directionas shown in FIG. 3b. This will produce a returning force (arrows 35 ofFIG. 3b)

upon the hook-like ends 22, causing them to seat flush upon surfaces 32as shown by arrows 36 in FIG. 30, when pressure is no longer applied totabs 26 as in FIG. 30.

Thus. the coupling 12 is caused to be readily conl() nected to driveshaft 16. In order that the coupling 12 be disconnected from shaft 16,the tabs 26 are depressed as shown by arrows 28 of FIG. 2a, and theprinting disc is unseated from shaft 16 (bore 14 is lifted outwardlyfrom the hub Thus. the coupling I5 12 is just as easily disconnected asit is connected to shaft 16.

The coupling can be made as a separate unit, and then attached to thecenter section of the printing disc, or the disc 10 and coupling 12 maybe molded integrally ofa flexible plastic such as: (a) acetalhomopolymer; (b) acetal copolymer; or (c) polypropylene.

The coupling of this print disc invention can naturally take on severaldifferent forms and modification not inconsistant with the quick connectand disconnect objectives outlined herein.

Therefore, it is considered that all such changes and modificationswhich would be obvious to the skilled practitioner be deemed to liewithin those limits encompassing the invention.

The full spirit and scope of the invention should be interpreted withrespect to the appended claims.

What is claimed is:

1. A one-piece flexible plastic coupling integrally formed with aprinting disc and being operable to quickly connect or disconnect saidprinting disc to and from a rotative hub ofa printing machine, said hubhaving abutting surfaces with which said coupling is engageable. saidflexible coupling comprising a center section seatable upon the hub ofsaid printing machine. two flexible arm members extending outwardly fromthe center section, said flexible arm members having a spring-likeresiliency which enable them to bend and flex in a spring-like manner,and a substantially rigid flange disposed upon each of said flexible armmembers in juxtaposition with said center section, each said flangehaving a finger tab end and a coupling end, each said finger tabreceiving pressure applied thereto for the purpose of causing saidflexible arms to flex and bend, each said coupling end of each saidflange riding over one of said abutting surfaces of said hub duringassembly when said center section of said coupling is caused to beseated upon the rotative hub and the flexible arms are caused to bend.said printing disc locking upon said rotative hub of said printingmachine after the coupling ends of said flanges ride over said abuttingsurfaces of said hub.

2. A printing assembly containing a quick connect and disconnectcoupling, said printing disc assembly comprising:

a rotative drive shaft for rotatively moving a printing disc coupledthereto. said drive shaft having a hub portion and abutting surfacesupon which the printing disc is made to lock thereon; and

a printing disc having a plurality of flexible arms radially extendingfrom a central disc section. each of said arms containing a charactertype at an outer end thereof. said printing disc having a quick con- 5 6nect and disconnect coupling disposed within said pressure to saidflange members causing the flexicentral disc section and integrallyformed thereble members of said coupling to flex and allow the with,said coupling comprising two flexible memcoupling means of said flangemembers to lock bers each supporting a substantially rigid flange uponsaid abutting surfaces of said drive shaft.

member, said flange members each having locking 5 3. The printing discassembly of claim 2, wherein the means for locking upon said abuttingsurface of locking means of each said flange member is a hook said driveshaft when said printing disc is assembled member.

thereto, said coupling being operative by applying

1. A one-piece flexible plastic coupling integrally formed with a printing disc and being operable to quickly connect or disconnect said printing disc to and from a rotative hub of a printing machine, said hub having abutting surfaces with which said coupling is engageable, said flexible coupling comprising a center section seatable upon the hub of said printing machine, two flexible arm members extending outwardly from the center section, said flexible arm members having a spring-like resiliency which enable them to bend and flex in a spring-like manner, and a substantially rigid flange disposed upon each of said flexible arm members in juxtaposition with said center section, each said flange having a finger tab end and a coupling end, each said finger tab receiving pressure applied thereto for the purpose of causing said flexible arms to flex and bend, each said coupling end of each said flange riding over one of said abutting surfaces of said hub during assembly when said center section of said coupling is caused to be seated upon the rotative hub and the flexible arms are caused to bend, said printing disc locking upon said rotative hub of said printing machine after the coupling ends of said flanges ride over said abutting surfaces of said hub.
 2. A printing assembly containing a quick connect and disconnect coupling, said printing disc assembly comprising: a rotative drive shaft for rotatively moving a printing disc coupled thereto, said drive shaft having a hub portion and abutting surfaces upon which the printing disc is made to lock thereon; and a printing disc having a plurality of flexible arms radially extending from a central disc section, each of said arms containing a character type at an outer end thereof, said printing disc having a quick connect and disconnect coupling disposed within said central disc section and integrally formed therewith, said coupling comprising two flexible members each supporting a substantially rigid flange member, said flange members each having locking means for locking upon said abutting surface of said drive shaft when said printing disc is assembled thereto, said coupling being operative by applying pressure to said flange members causing the flexible members of said coupling to flex and allow the coupling means of said flange members to lock upon said abutting surfaces of said drive shaft.
 2. A printing assembly containing a quick connect and disconnect coupling, said printing disc assembly comprising: a rotative drive shaft for rotatively moving a printing disc coupled thereto, said drive shaft having a hub portion and abutting surfaces upon which the printing disc is made to lock thereon; and a printing disc having a plurality of flexible arms radially extending from a central disc section, each of said arms containing a character type at an outer end thereof, said printing disc having a quick connect and disconnect coupling disposed within said central disc section and integrally formed therewith, said coupling comprising two flexible members each supporting a substantially rigid flange member, said flange members each having locking means for locking upon said abutting surface of said drive shaft when said printing disc is assembled thereto, said coupling being operative by applying pressure to said flange members causing the flexible members of said coupling to flex and allow the coupling means of said flange members to lock upon said abutting surfaces of said drive shaft. 